ABSTRACT
A geometrical and microscopic mixing index defined by the contact number was used to study the transverse mixing in a Kenics motionless mixer. The mixing index, a measure of transverse mixing, increased exponentially as the number of helices in the motionless mixer increased. The helices in the mixer also had the significant effect of reducing the void fraction of the mixture. The relationship between the coordination number and the compaction in the mixture through the mixer was studied. The mean coordination number indicates that the packing of these mixtures are between the cubic and hexagonal packings.